Science Weather Chapter 7

Front 1

isobars

Back 1

a contour line of equal or constant pressure on a graph, plot, or map.

Front 2

milibar

Back 2

A unit of atmospheric pressure equal to one thousandth (10 -3) of a bar. Standard atmospheric pressure at sea level is about 1,013 millibars.

Front 3

weather system

Back 3

The state of the atmosphere at a given time and place, with respect to variables such as temperature, moisture, wind velocity, and barometric pressure.

Front 4

high pressure system

Back 4

aka an anticyclone

Front 5

anticyclone

Back 5

aka the high pressure system

Front 6

low pressure system

Back 6

aka a cyclone

Front 7

cyclone

Back 7

akathe low pressure system

Front 8

mighty masses

Back 8

aka air mass a large quantity of air sharing the same characteristics

Front 9

continental polar

Back 9

(abb) cP air mass comes from northern canada

Front 10

maritime polar

Back 10

(abb) mP also means from the ocean. comes from thr north of atlantic or north pacific,

Front 11

continental tropical

Back 11

(abb) cT from mexico

Front 12

maritime tropical

Back 12

(abb) mT from the gulf of mexico, the tropical atlantic, or the tropical pacific

Front 13

clod front

Back 13

cold air advancing

Front 14

warm front

Back 14

warm air advancing

Front 15

stationary front

Back 15

none advancing

Front 16

occluded front

Back 16

if a cold front overtakes a warm front

Front 17

frontal low

Back 17

a low originating along a frontal line

Front 18

cumuloninbus cloud

Back 18

aka thunderhead

Front 19

squall lines

Back 19

the long lines of a thunderstorms that may form in the warm air ahead of a moving cold front

Front 20

updraft

Back 20

a strong upward air current ascending at speeds that may exceed 100 mph

Front 21

downdrafts

Back 21

strong downward air currents

Front 22

step leaders

Back 22

downward, negatively charged channels

Front 23

streamer

Back 23

an upward, positively charged return stroke

Front 24

waterspout

Back 24

a tornado forming over a body of water *danger danger* do not go near any twister, funnel or waterspout *deadly dangerous*

Front 25

supercell

Back 25

an unusually large cumulonimbus

Front 26

wallcloud

Back 26

a rotating mass of cloud

Front 27

trade wind inversion

Back 27

beginning at a certain altitude above the trade-wind zones, air temperatuer rises with altitude, producing a layer of air

Front 28

tropical depression

Back 28

a baby hurricane

Front 29

tropical storm

Back 29

a storm with winds going at 39 mph

Front 30

tropical cyclone

Back 30

wind speed at 75 mph aka a typhoon in the pacific ocean, a willy-willy in australia, and a hurricane in america and the west indies

Front 31

five most important properties of air

Back 31

1:temperature,2:pressure,3:humidity,4:wind direction,5:wind speed

Front 32

meteorologists

Back 32

scientists who study the weather

Front 33

thermometer

Back 33

An instrument for measuring temperature

Front 34

thermograph

Back 34

records the temperature it indicates

Front 35

barometer

Back 35

An instrument for measuring atmospheric pressure, used especially in weather forecasting

Front 36

standard pressure

Back 36

the average air pressure at sea level

Front 37

hygrometer

Back 37

Any of several instruments that measure atmospheric humidity

Front 38

psychrometer

Back 38

An instrument that uses the difference in readings between two thermometers, one having a wet bulb and the other having a dry bulb, to measure the moisture content or relative humidity of air

Front 39

wet-bulb depression

Back 39

The difference in degrees between the dry-bulb temperature and the wet-bulb temperature.

Front 40

hygrograph

Back 40

An automatic hygrometer that records variations in atmospheric humidity